In recent years, automated clutches have become more and more widespread. Comfort and safety are being increasingly enhanced through the use of sensor technology and electronically initiated interventions in the driving procedure.
It is known from vehicle technology to use at least one clutch actuator to actuate a clutch in an automated transmission. If absolute displacement is not used with the clutch actuator, incremental displacement measuring can be provided, which accordingly has incremental displacement measuring sensors. When so-called EC motors are used, these incremental displacement measuring sensors are integrated directly into the motors.
It has been found that the incremental displacement measuring system should be balanced regularly. When balancing the incremental displacement measuring system, a calibration point can be approached and scanned, with the position of the calibration point being used as the point of origin or clutch reference position for balancing the incremental displacement measuring system.
A control device for a motor vehicle friction clutch is proposed in DE 44 33 825 C2. This control device includes a drive, a transmission which transforms the motion of the latter into an essentially linear motion of an output element, the range of motion of the transmission in the possible direction of motion being limited by at least one stop operating in those directions, and a clutch position control. The clutch position control has a monitoring device, in which a measuring device checks the drive for energy supply and effective direction of the supplied energy, and an incremental sensor monitors changes in position of the transmission. If an inflow of energy at the drive does not result in a change of position at the incremental sensor, this proves that the stop located in the effective direction has been reached, and results in the position reached being established as the new stop position in the measuring device.
In DE 100 27 330 A1 a method for operating a torque transfer device is proposed. In so doing, it is reviewed whether a movably situated circuit element which has been under load is in a selector position that corresponds to the position of a limit stop or that corresponds to a selector position that is within a tolerance range which is situated around a target selector position. If this is the case, a low relief voltage is applied for a predetermined brief time period by the control device. The movement of the movably situated circuit element produced by this relief signal is directed in particular away from an end stop. The relief voltage at least partially overcomes self-locking forces of the electric motor or actuating mechanism or the like, so that a corresponding motion of the circuit element is produced.